Precision agriculture and IoT technologies

Precision agriculture (PA) is one of the most well-known applications of IoT in the agricultural sector and numerous organizations are leveraging this technique around the world. PA employs technologies like GNSS, VRT and drones that are connected through remote sensors to measure spatial variability, communicate farm conditions, plan irrigation and harvesting, and thus eliminate human intervention to a large extent.

In IoT-based PA, data from the sensors can be shared with the stakeholders either through a local server or the cloud, depending on the reliability of the communication network and Internet connectivity.

These data are accessed via smartphones, and user-friendly apps can be used to represent the data in a simple and clear format.

In PA, the fields are treated applying variable rates of inputs (irrigation water, fertilizers, pesticides, etc.) according to the actual needs of each location in the field.

In this way the efficiency is increased, and yield, quality and impact on the environment are optimized.

4.1.2.1 Guidance systems (GNSS and RTK) Guidance systems form the generic backbone technology for PA. They can be used by all kinds of equipment (e.g.

tractors, combine-harvesters, sprayers, planters, etc.) and as part of a broad range of different agricultural applications. Guidance systems focus on precise

positioning and movement of a machine with the support

of a Global Navigation Satellite System (GNSS). The equipment is becoming so smart that drivers barely have to do anything at all to get from Point A to Point B. Machines also till, plant, and apply fertilizer and pesticides while traversing those straight lines using a steering system. Even the most experienced drivers can make mistakes, but auto-steer takes the human error out of the equation in a way that has major benefits for farmers working their fields.

Guidance systems are most often used on tractors.

Combine-harvesters are also being fitted with guidance systems to help keep equipment precise. While these systems are not standard equipment on new tractors, most are guidance system-ready, requiring additional investment in a GPS receiver with the level of spatial resolution desired. Guidance systems enable auto-steering, precise machine movement between plant rows, precision drilling and sowing, precision spraying and mechanical weeding.

Adoption of PA technology naturally leads to greater expenditures on machinery and equipment as these technologies are capital-intensive. Machinery also has a higher expense base (compared with labour costs) and more potential to influence overhead costs. Economic payback through field efficiency is critical for a farmer’s decision to adopt guidance systems, but there are a number of other benefits that guidance systems are bringing to the end user.

Guidance systems work day or night, allowing faster, safer and more accurate field operations even when visibility is very low. This allows the user to get in the field whenever it is convenient, or to work around light and weather conditions that would be impossible with traditional guidance. Because the guidance system takes care of itself, the operator can watch other important operations, such as the condition of the crop, monitor feedback, the condition of the implements and obstacles in the field. Correcting a malfunctioning implement in the field can, in itself, enhance the steering product payback.

Because a guidance system puts farm implements on the most efficient course, it means the job will get done more quickly, and, clearly, the less time farm equipment runs, the less fuel will be used. Fuel expenses are just one way that guidance systems pay for themselves. Lowering the input costs is another way that farmers can save money.

Farmers will spend less money on seed and less money on labour as the job will be done more efficiently and more quickly. An hour here or a few hundred seeds there all add up over the course of a season.

Although this technology was introduced in the early 1990s, significant studies at global level of the impact of guidance systems in agriculture are not yet available. To date, only individual research cases, mostly in the United States and Europe are measuring the impact of adoption and implementation on the field. An example is the work

CASE 3 USE OF AUTO-STEERING ON CROP AND SOYBEAN FARM IN THE UNITED STATES

MIDWEST LITMUS TEST

Substantiating a payback for Midwest row crop use of guidance system was a primary goal last year for ag economists at Purdue University. Jess Lowenberg-Deboer and then graduate student Matt Watson designed a study to evaluate and compare the economic impacts of using no guidance versus manual lightbar guidance, DGPS-based guidance, and higher accuracy real time kinematic (RTK)-based steering systems on a 1800 acre farm with a 50–50 corn–soybean rotation.

Using a 12-row planter, each system was measured on its ability to improve field efficiency and reduce skip and overlap, increase the number of hours worked and use techniques to control traffic patterns such as skip rows to increase efficiency.

The results were dramatic. Whereas manual guidance increased field speed by 13 percent, DGPS and RTK systems increased speed by 20 percent. Mean time spent in the field was reduced 11 percent using manual guidance, and an additional 6 percent using DGPS and RTK systems.

Doing the maths, Purdue determined that the same 12-row planter could handle an additional 800 acres in the given time frame using manual lightbar guidance, and an additional 1300 acres with GPS and RTK steering systems. Finally, and most importantly, grower net profits would be expected to increase by $9,700 annually using GPS steering systems and $4,500 for the more expensive, higher accuracy RTK steering systems.

Source: www.precisionag.com/in-field-technologies/guidance/automatic-steering-precision-agricultures-killer-app/

of Shockley et al. (2011), which modelled a commercial Kentucky corn and soybean farm under no-till conditions and applied a guidance system during planting and fertilizer application, resulting in cost-savings of approximately 2.4 percent, 2.2 percent and 10.4 percent for seed, fertilizer and tractor fuel, respectively, which is translated to greenhouse gas emission mitigation.

Guidance systems such as lightbar and auto-steering can benefit crop growers by reducing working hours of operators in the field by 6.04 percent and reducing fuel consumption by 6.32 percent (Bora, Nowatzki and Roberts, 2012). In peanut digging operations, a study in Alabama during the 2005–2007 growing seasons revealed average net returns between 83 and 612€/ha for the use of auto-steering (Ortiz et al., 2013). An economic analysis of farms adopting guidance systems showed that systems with inaccuracies below 2.5 cm are most profitable for larger farms, while systems with less than 10 cm inaccuracy are a better economic alternative for smaller farms (Bergtold, Raper and Schwab, 2009).

The economic benefits of guiding systems in the UK were estimated for a 500 ha farm to be at least at 2.2€/

ha (Knight, Miller and Orson, 2009), but the benefits grow if other more complex systems are adopted, such as controlled traffic farming (CTF) (2–5 percent), which would lead to additional returns of 18–45€/ha for winter wheat cultivation. In Germany, economic benefits from savings of inputs were assessed at 27€/ha for the case of winter wheat. CTF typically releases 57–115 €/

ha extra profit, including the required investment, cost savings and increased yields.¹⁰⁷ The implementation of GNSS provides economic advantages of up to 28€/ha from input savings (Shockley et al., 2012). If a guidance system is already installed, the economic advantage of the automatic section control is even higher. Using CTF can decrease fertilizer use by 10–15 percent for narrow-spaced crops and pesticide reduction can reach 25 percent. Tullberg (2016) has analysed the impact of CTF in GHG emissions directly and indirectly, by reducing energy inputs, facilitating zero tillage and increasing fertilizer efficiency. Primarily, he referred to an approximate reduction of tractor fuel requirements of 40 percent and 70 percent while using uncontrolled traffic zero tillage and controlled traffic zero tillage farming, respectively, in comparison with conventional tillage.

Horsch Company (Balafoutis et al., 2017) pointed out that fuel use for crop establishment with CTF is reduced by at least 35 percent, while Jensen et al. (2012) estimated that it may be possible to reduce costs of fuel by 25–27 percent in cereals because of less overlap.

Although the economic impact of guidance systems is clear, they are expensive and not all farmers can afford them. Farmers identify up-front cost as the most frequently mentioned disadvantage of machine guidance.

Guidance systems have scalable cost according to the accuracy obtained from each system. The cost starts from 1,320€ if a GNSS device is already held by the farmer. Commercial applicators that require a system to combine recording of all operations (to different customers) together with full navigation can reach more than 12,770€ (Grisso et al., 2009). In countries where most of the farmers are earning less than US$2 per day and cultivate less than 2 ha, these technologies are not profitable. More affordable could be VRT combined with UAV application services provided by companies, thus costs will be decreased and such services are available for smallholders.

4.1.2.2 Variable rate technology (VRT) VRT in PA is an area of technology that focuses on automated application of materials to a given landscape.

The way in which the materials are applied is based on data collected by everything from drones and satellites, AI, IoT and hyperspectral imaging. These materials include fertilizers, chemicals, seeds and water, with all aiming to optimize crop production. There are many forms of technology used in VRT for PA. VRI stands for precision irrigation, VRS for precision seeding, VRNA for precision nitrogen fertilizer application and VRPA for precision pesticide application. Regardless of which variable rate application technology is used, it is important to understand the general way in which this technology is applied.

The capital cost of farm implements equipped with VRT capabilities is fairly high, especially when specialized machinery with integrated sprayer or seeding equipment must be scrapped. For this reason, many producers, particularly smallholder farmers, have opted to hire service providers when choosing VRT. With the fast pace of IoT development and price decrease of the equipment for irrigation, a more feasible option for smallholder farms is VRI that optimizes maximum profitability on irrigated crop fields with topography or soil variability, improves yields and increases water use efficiency (Case 4).

A VRT system can help to automate the agricultural process. The more automation and precision that a farm introduces to its operations, the more money can be saved through higher production and efficiency. Multiple sources, project-based and mostly large-scale farms from developed countries present various economic benefits of VRT.

Applying VRI mostly has impact from an environmental point of view. The contribution of VRI to GHG emission abatement lies in reduction of water, leading to lower pumping energy needs and proper irrigation scheduling, preventing extreme soil water availability to boost N₂O

CASE 4 APPLYING SMART IRRIGATION SYSTEM IN GREECE BASED ON FAO METHODOLOGY

IRMA_SYS

IRMA_SYS operates at the plain of Arta (Region of Epirus, Greece). The main objective of the project is to provide recommendations to farmers on irrigation management through use of an integrated IoT system, with the aim of optimizing use of water and energy and saving labour. More precisely, IRMA_SYS uses ICT to collect, store and process necessary data from point sources (agrometeorological stations) and transform them to maps that cover a big area. In this way, basic weather data and reference evapotranspiration are available for each point inside the covered area. This information is then combined with information provided by the users for their fields and the irrigation events they apply, to provide irrigation management recommendations. IRMA_SYS covers the 20 000 ha of the Arta plain in Greece. It uses real time (10-min averages) data from six agrometeorological stations, that were deliberately placed, after a relevant study, all around the area covered. Data are sent via VHF and GPRS to a communication centre, which is connected to the system’s server. All this information, along with data concerning irrigation events (inserted by the user) and weather forecast data (provided by the National Observatory of Athens (on a 6.5×6.5 km grid basis), is used to estimate irrigation water requirements on hourly and daily time steps. A modification of the FAO Penman-Monteith method is used by the software for this task. All the software has been developed as open source. The service is available in both Greek and English languages.

IRMA_SYS leads to conscious building regarding rational water use in the framework of irrigation. The users understand the significance of knowing basic facts about their irrigation system (flow rate, uniformity, etc.), the ability of each soil type to store water and the actual crop water needs. Use of the system leads to water savings (which are more significant for high water-consuming crops, for example it is 5 percent for olives, 15 percent for citrus and at least 30 percent for kiwi-fruits) and the respective energy and labour savings. For example, the kiwi-fruit crop covers an area of 1200 ha at Arta and needs 600 000 m³ of water for irrigation every year. IRMA_SYS already provides potential savings of at least 30 percent for this crop, which corresponds to around 200 000 m³ of water per year. In addition, irrigation water management organization in the area where IRMA_SYS is applied can be used to document decisions regarding water allocation in other participatory systems managed in the same area.

The installation cost of IRMA_SYS (IRMA_SYS in not to be installed in single fields) varies between 5 and 20€

per hectare depending on the terrain, the number of crops in the area, the availability of agrometeorological stations and background information (i.e. soil maps, etc.). The annual maintenance cost has to be calculated individually for each case, but to give an idea of the cost, for the plain of Arta (an area of 20 000 ha in which the system currently operates), this is 60000€ per year. Use of IRMA_SYS does not require any hardware at the field. After the setting of each field, the user needs only a mobile phone or a computer, etc., to input the irrigation event data and to access the recommendations. Thus, the system is available to all interested, which makes it socially fair.

Source: http://irmasys.eu/

emissions. Computer simulation studies comparing conventional and “optimized” advanced site-specific zone control by centre pivot irrigation have reported water savings of 0–26 percent (Evans et al., 2013).

VRI systems can provide 8–20 percent reduction in irrigation water use (Sadler et al., 2005). La Rua and Evans (2012) using centre pivot speed control determined that irrigation efficiency (the ratio between irrigation water actually used by growing crops and water diverted from a source) can be increased by more than 5 percent.

If speed control is also combined with zone control,

then the irrigation efficiency can be further improved by 14 percent. The HydroSense project (HydroSense 2013) applied VRI in three experimental fields with cotton in Greece and showed that variable irrigation in cotton cultivation achieved 5–34 percent savings in water consumption. Lambert and Lowenberg-DeBoer (2000) reported economic benefits through use of VRI, because of higher corn yields and better water use efficiency;

however, these benefits were not quantified. As

mentioned above, VRI systems can add significant costs to the farm, but additional benefits have been identified after installation of such systems, such as possible yield

increase, workload reduction, water use decrease and even pesticide use saving, especially in climatically unfavourable years such as in big droughts (Booker et al., 2015; Evans & King 2012).

A review by Trost et al. (2013) compared N₂O emissions from irrigated and non-irrigated fields showing

an increase of N₂O emissions (about 50 percent to 140 percent) under irrigation, in most case studies. This

shows that VRI may significantly influence N₂O emission from irrigated soils. VR irrigation systems can also assist irrigation scheduling combined with meteorological prediction models and fertilization schedules to keep soil water availability at such levels to avoid provoking more GHG emission production through N₂O.

VRS of winter wheat can increase yield from 3 percent compared with uniform seeding.¹⁰⁸ Another study

showed that farmers using VRS have achieved an average winter wheat yield benefit of 4.6 percent over and above farmers drilling at a flat rate. This makes an average winter wheat yield benefit over the four years of study (2011–2014) of 6.45 percent (European Parliament, 2014).

Corn yields can be increased by 6 percent using VRS.¹⁰⁹ Several authors have analysed the impact of VRNA on farm productivity and economics. Tekin (2010) estimated that VRNA can increase wheat production between 1 percent and 10 percent, offering savings in nitrogen fertilization between 4 percent and 37 percent. Mamo et al. (2003) executed an experiment for three years (1995, 1997, 1999) in corn fields in rotation with soybean in Minnesota, USA, and found a profit increase of 7 to 20.25 €/ha for corn when using VR fertilizer application compared with uniform application because of a reduction in the use of fertilizer.

There has been significant interest in the amount of pesticide that can be saved, reported to range from 11 percent to 90 percent for herbicide use in different arable crop types (Timmermann et al., 2003; Gerhards et

CASE 5 IOT FOR WATER IRRIGATION IN SOME LATIN AMERICAN COUNTRIES

IMPROVING WATER USE IN DRY AREAS Telefónica and FAO

Application of the IoT the digital interconnection of everyday objects to the Internet to the agricultural sector aims to optimize processes and make more efficient use of natural resources. FAO and Telefónica are working on a pilot water efficiency project with communities in El Salvador and Colombia, using a combination of specialized hardware, cloud storage and data processing that generates recommendations to facilitate decision-making for farmers on issues related to irrigation for efficient use of water.

The first four relate to crops of cucumber, bell peppers, papaya and tomato in different districts of El Salvador, and were launched in September. This will be followed by two cotton projects in Peru, and a potato project in Colombia during October. And, finally, in November the FAO and Telefónica will launch projects focused on avocado and plantain in Colombia.

The pilots will run at least until the end of 2019 so that results can be compared from one year to the next, although some crops can be repeated twice a year or more. The FAO’s partnership with Telefónica consists of a first phase running through 2021. Telefónica has claimed 20 percent savings in water and power for irrigation as a result of AI technology developed at its R&D centre in Chile.

Source: https://www.bnamericas.com/en/news/ict/telefonica-and-fao-launch-latam-water-efficiency-pilots

al., 1999). Other work recorded pesticide use reduction in perennial crops at between 28 percent and 70 percent (Solanelles et al., 2006; Chen et al., 2013). VRPA can also cause reductions in insecticide use by 13.4 percent in winter wheat (Dammer & Adamek 2012), while spray overlap can be significantly decreased with impact on the total pesticide use (Batte & Ehsani, 2006). The impact of the high pesticide reduction shown from the literature is environmentally significant, but, in terms of GHG emission reduction, the contribution of this technology to the total agricultural effect is slight.

To conclude, in smallholder farms, savings are highest from VRT because they optimize all inputs such as seeds, water, fertilizer and pesticides. Guidance systems can assist VRT but are also helpful for crop production by themselves.¹¹⁰ Some PA technologies are already highly

To conclude, in smallholder farms, savings are highest from VRT because they optimize all inputs such as seeds, water, fertilizer and pesticides. Guidance systems can assist VRT but are also helpful for crop production by themselves.¹¹⁰ Some PA technologies are already highly